Republican congressmen vented Wednesday that a signature aspect of President Barack Obama’s financial reform has become too costly and complex to enforce.

The so-called “Volcker Rule”— named after former Federal Reserve Chairman Paul Volcker — would restrict banks from trading for their own accounts, a move intended to prevent them from making risky bets with deposits insured by the government.

At a joint House Financial Services subcommittee hearing, Rep. Spencer Bachus (R-Ala.) attacked the rule as being a “self-inflicted wound” for the entire economy, warning that Wall Street jobs could migrate abroad to Canada after the rule starts to go into effect in July.

The Volcker Rule asks the government to distinguish between banned “proprietary trading” and legitimate “market making,” or trades that smooth out the process of buying and selling investments like stocks and bonds.

Federal regulators recently issued a 300-page proposal for enforcing the rule that contains more than 1,300 questions, an effort easily interpreted as revealing the challenge of spotting the newly forbidden trades.

“Making such distinctions will be difficult, if not impossible,” said Bachus, chairman of the Financial Services committee.

Rep. Michael Grimm (R-N.Y.) ripped into the regulators who appeared at the hearing, dubbing them “overzealous” bureaucrats who have “found creative ways to make a terrible rule even worse.”

Rep. Barney Frank (D-Mass.) defended the proposal drafted by the Federal Reserve and the Securities and Exchange Commission, among other regulators who appeared at the hearing.

The exhaustive draft tries to address worries by banks that the Volcker Rule might penalize market-making trades and cause liquidity to dry up, he argued.

“You are guilty of trying to accommodate some of the concerns that financial institutions have,” concluded Frank, a namesake of the 2010 Dodd-Frank financial reform that features the rule.

Democrats vying to succeed Frank, who has announced plans to retire at the end of his term as the committee’s ranking member, did raise questions about the impact of the measure.